Illumination systems employing laminated sheet-form optical structures with embedded TIR channels

An illumination system, comprising:

• a light source comprising a plurality of LEDs;
• a first layer of an optically transmissive material;
• a second layer of an optically transmissive material superimposed on and bonded to the first layer using an optically transmissive adhesive;
• a first linear array of parallel channels formed in the first layer;
• a second linear array of parallel channels formed in the second layer;
• an optical sheet comprising a two-dimensional pattern of light diffusing surface microstructures;
• and
• a broad-area reflective surface configured to reflectively scatter light,
• wherein the second linear array of parallel channels extends at an angle with respect to the first linear array of parallel channels,
• wherein the first linear array of parallel channels defines a plurality of linear prismatic surface structures protruding away from the first layer and longitudinally extending along straight parallel lines from a first edge of the first layer to a different second edge of the first layer,
• wherein each of the plurality of linear prismatic surface structures has a first wall and a second wall contiguous with the first wall and disposed at a right angle with respect to the first wall,
• wherein the first wall is configured to reflect light using total internal reflection, and
• wherein the first layer and the second layer form a flexible laminated sheet-form structure having a generally rectangular shape and a thickness between 200 micrometers and 1 millimeter.

An illumination system, comprising:

• a light source comprising a plurality of LEDs;
• a first layer of an optically transmissive material;
• a second layer of an optically transmissive material superimposed on and bonded to the first layer using an optically transmissive adhesive;
• a first linear array of parallel channels formed in the first layer and longitudinally extending along straight parallel lines from a first edge of the first layer to a different second edge of the first layer;
• a second linear array of parallel channels formed in the second layer and longitudinally extending along straight parallel lines at an angle with respect to the parallel channels of the first linear array;
• an optical sheet comprising a two-dimensional pattern of light diffusing surface microstructures;
• and
• a broad-area reflective surface configured to reflectively scatter light,
• wherein at least some of the parallel channels formed in the first layer are separated from one another by surface portions which are generally parallel to a plane of the first layer,
• wherein each of the parallel channels of the first linear array has a surface which is disposed at an angle with respect to a plane of the first layer and is configured to reflect light using total internal reflection, and
• wherein the first layer and the second layer form a flexible laminated sheet-form structure having a generally rectangular shape and a thickness between 200 micrometers and 1 millimeter.